Prevent Listeria Infection This Summer

Unlike most bacteria, Listeria can grow in a cold refrigerator, experts warn

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SUNDAY, June 9, 2013 (HealthDay News) -- With the arrival of summer, many folks think they can keep their picnic food safe from bacteria by storing it in the refrigerator.

But they would be wrong about one bacteria.

Unlike most of its brethren, Listeria bacteria can grow in cool temperatures. Refrigerating food contaminated with this bacteria could allow the germs to multiply and spread, according to the U.S. Food and Drug Administration.

The bacteria can cause a serious illness known as listeriosis, which is particularly dangerous for children, older people, pregnant women and those with compromised immune systems or chronic medical conditions, such as diabetes.

Foods in which Listeria has been found include deli meats, hot dogs, smoked seafood and store-prepared salads. The FDA advises those at greater risk for developing listeriosis to reheat these ready-to-eat foods until they are steaming hot. They should also avoid unpasteurized milk and soft cheeses.

Listeriosis has also been linked to contaminated cantaloupes. The FDA recommended washing all fruits and vegetables under running water immediately before eating, cutting or cooking them. Firm produce, in particular, should be scrubbed with a produce brush.

The FDA added that other ways to prevent Listeria infection include:

Set your refrigerator temperature to 40 degrees Fahrenheit or lower to inhibit or slow the growth of Listeria. Use a refrigerator and freezer thermometer to ensure temperatures are sufficiently cold.

Wrap or cover food before placing it in the refrigerator. Be sure no containers or covers are leaking juices on other foods.

Do not allow cooked or ready-to-eat foods to sit in the refrigerator. Eat these foods right away so Listeria doesn't have the opportunity to grow. "If you have leftovers in your refrigerator, it's best to throw them out after three days, just to be sure," Donald Zink, senior science advisor at FDA's Center for Food Safety and Applied Nutrition, said in a news release. "It's better to be safe than sorry."

Clean up refrigerator spills immediately. The FDA notes leaks or spills from hot dog packages, raw meat or poultry are particularly worrisome. The agency advised cleaning these spills with paper towels to avoid spreading germs to a cloth towel.

Routinely disinfect the refrigerator. The FDA recommended cleaning the inside walls and shelves of the refrigerator with warm water and soap. Surface cleaners can also be used monthly.

Sanitize kitchen surfaces where food is prepared with soap and water and surface cleaner. The FDA noted homemade sanitizer can be made by combining one teaspoon of unscented bleach with one quart of water. Unused bleach solution should be discarded since it becomes less effective over time.

Wash cutting boards after every use. Nonporous acrylic, plastic, or glass boards can be sanitized in the dishwasher.

Wash dish cloths, towels and cloth grocery bags in the hot cycle of the washing machine.

Before and after handling food, wash your hands with warm water and soap.

More information

The U.S. Centers for Disease Control and Prevention provides more information on Listeria.